Acglutinant



Patented & Jan. 2, 1934 UNITED STATES AGGLUTmANT Willy Stelkens,Cologne, and Richard Miiller,

Mannheim, Germany,

assignors to C.

Boehringer & Soehne G. m. b. H., Mannheim- Waldhof, Germany No Drawing.Application August 9, 1930, Serial No. 474,301, and in Germany August12, 1929 13 Claims. 8717) Our invention refers to agglutinants, moreespecially such as are insoluble in water and have the form of a powderor a folia, which consists largely of a cellulose derivative, such asfor instance a cellulose ester, acetyl cellulose, nitro cellulose or thelike. An agglutinant of this kind, if inserted in dry condition betweentwo pieces of leather and heated or moistened with a solvent for theagglutinant or both, will cement the two pieces together.

We have now ascertained that the time required for obtaining a fulleffect of the agglutinant can be considerably reduced and at the sametime the tearing resistance can be greatly increased if, instead ofusing a powder or folia formed of one or a plurality of ordinary plasticagglutinants, a mixture is used, which is composed of constituentshaving difierent, well defined characteristics.

We have found that a ready softening and setting and a permanentadherence of the surfaces to be cemented can be obtained if theagglutinant is composed of at least two cellulose derivatives, each ofwhich has the adhesion characteristics of an agglutinant, under theinfluence of a solvent or swelling medium or of heat or both, not onlyas far as the surfaces to be cemented are 'concerned, but also withregard to the other component or components constituting thecomposition, while at the same time differing, as far as these adhesioncharacteristics are concerned, from one or several of the othercomponents (if more than two components are present). While it isdesirable that the solidity of fixation obtained be as great as possiblein all components, we have found it advantageous that they differ inrespect of the period of time required for swelling or softening and forsetting.

Agglutinants composed of a plurality of components of differentcharacter will react difierently towards solvents as well as uponheating. That component, which swells or softens more readily, willquickly create a bond between the surfaces to be cemented, while anothercomponent, which swells or softens less readily and forms with thesolvent a solution of higher viscosity, will act like a lattice orframe-work,- first whether they are chemically well defined comofferinga mechanical support to the more readily swelling and softeningcomponent or filler, preventing deliquescence thereof, but thereaftergradually swelling also and, in doing so, gradually absorbing thecementing layer of the other component into its own cementing layer anduniting with it. v

The term "component, as here used, is meant to include homogeneoussubstances, no matter pounds, such as for instance cellulose esters orethers, or mixtures, such as celluloid or other cellulose derivativescombined with softening means to form homogeneous masses.

Taking this into account, agglutinants according to the presentinvention, which form binary or higher mixtures, may for instance becomposed of celluloid and nitro-cellulose or of celluloid andgelatinized acetyl cellulose or of two or more kinds of celluloidrecovered from nitro celluloses of different viscosity. Gelatinzing,softening and/or dissolving agents may be added, which may facilitatethe swelling and softening of one or all components.

The new agglutinants according to the present invention are fit forcementing together materials of the same or of widely diiferingcharacter, for instance leather, paper, cardboard, textile materials,wood, metal, glass, porcelain, etc. Shoe soles, doubled webs of fabric,plywood, metallized cable envelopes, insulating layers andnon-splintering glass plates can be manufactured wit the aid of theseagglutinants.

The selection of the components with respect to their swelling capacity,viscosity etc. so that they can either act as frame-work substances oras fillers, depends upon the nature of the materials to be cemented,upon the pressure and temperature admissible during fixation, upon therequirements of cementing speed and strength and the like, and can bedetermined in a simple manner by experiment for each individual case.

The following table contains a small number of particularly usefulcompositions according to this invention.

Framework substances 7 Fillers Soitened by means of Particularly suitedfor cementing 50 Celluloid waste Nitrocellulose of high viscosity(collodion wool) Acetyl cellulose Nitrocellulose of low viscosity (about1% seconds) Nitrocellulose of low viscosity N itroeellulose Leather,textile material, paper Leather, textile material, paper Leather,textile materiel, wood Solvents for celluloid The agglutinants accordingto this invention can be obtained by simply mixing the finely powderedcomponents, which may be used as such or may be converted into foliaa,by compressing the powder to plates or blocks, which are then subdividedinto thin sheets or films by planing or otherwise. Foliw can howeveralso be produced by pouring or dissolving and kneading and mill- Example1 12 parts acetyl cellulose soluble in acetone and 3 parts ethylacetanilidon the one hand and 12 parts collodion wool and 3 parts ethylacetanilid on the other hand are dissolved in acetone. The two solutionsare first filtered separately and are then mixed. The mixture can beconverted into liquid folim by pouring, which can be used with solventsfor cementing leather, cardboard, textile materials or the liketogether.

Example 2 12 parts transparent celluloid waste are mixed with 8 parts ofnitrocellulose of low viscosity, such as is used for instance in themanufacture of lacquers applied by atomization. To the mixture is addeda solvent capable of dissolving both constituents and it is thenconverted according to one of the methods used in the manufacture ofcelluloid, into foliaa, which preferably serve for cementing'leather,textile materials and paper together without the application of heat, asuitable solvent being used.

The term softening medium used in the claims is intended to include alsoheat, solvents and swelling agents.

tics of an agglutinant with regard to the other.

component as well as to the material to be cemented, but differing fromthe other component in respect to the rate of softening.

2. As a new product, a solid agglutinant being a mixture of acetylcellulose, collodion wool and ethyl acetanilid.

3. As a new product, an-agglutinant in solid form comprising a pluralityof components of different softening properties intimately mixed withone another and each component, when acted upon by a softening medium,possessing the characteristics of an agglutinant with respect totheothers, at least two of said components being cellulose derivatives.

4. The product of claim 3 wherein said cellulose derivatives arecellulose esters.

5. The product of claim 3 wherein at least two of said components arecelluloid having different softening properties.

6. The product of claim 3 wherein one'of' said components is celluloidand another is nitrocellulose.

7. The product of claim 3 wherein one of said components is celluloidand another is low viscosity nitrocellulose.

8. The product of claim 3 wherein the said solid agglutinant is in theform of foliae.

9. The product of claim 3 wherein the said solid agglutinant is inpulverulent form.

10. As a new product, an agglutinant in solid form comprising at leasttwo cellulose ester components of difierent softening properties intimately mixed with one another and possessing, when acted upon by asoftening medium, the characteristics of agglutinants with respect toeach other, at least one of said esters being combined with aplastifying agent.

11. The product of claim 10 wherein said cellulose ester components arenitrocellulose.

12. The product of claim 10 wherein at least two of said cellulose estercomponents are nitrocellulose and one of said components is combinedwith a plastifying agent.

13. The product of claim 10 wherein at least two of said cellulose estercomponents are nitrocellulose and one of said components is combinedwith a greater amount of a plastifying agent than another of saidcomponents.

' WILLY STELKENS.

RICHARD MULLER.

